B.G 2.64 and 65
रागद्वेषविमुक्तैस्तु विषयानिन्द्रियैश्चरन्। आत्मवश्यैर्विधेयात्मा प्रसादमधिगच्छति ॥६४॥
प्रसादे सर्वदुःखानां हानिरस्योपजायते। प्रसन्नचेतसो ह्याशु बुद्धिः पर्यवतिष्ठति ॥६५॥
rāgadvēṣavimuktaistu viṣayānindriyaiścaran। ātmavaśyairvidhēyātmā prasādamadhigacchati ॥64॥
prasādē sarvaduḥkhānāṁ hānirasyōpajāyatē। prasannacētasō hyāśu buddhiḥ paryavatiṣṭhati ॥65॥
[ रागः द्वेषः विमुक्तैः तु विषयान् इन्द्रियैः चरन्। आत्म वश्यैः विधेय आत्मा प्रसादम् अधिगच्छति॥
rāgaḥ = passion; dvēṣaḥ = hatred; vimuktaiḥ = becoming free of; tu = but; viṣayān = the material topics; indriyaiḥ = in the 'indriyas'; caran = moves; ātma vaśyaiḥ = one has got it under his grasp; vidhēya ātmā = one who has made indriyas his servant; prasādam = serenity (of mind); adhigacchati = obtains;]
[ प्रसादे सर्व दुःखानां हानिः अस्य उपजायते। प्रसन्न चेतसो हि असु बुद्धिः परि अवतिष्ठति॥
rasādē = from grace; sarva = all; duḥkhānāṁ = miseries; hāniḥ = destruction; asya = his; upajāyatē = becomes possible; prasanna = serene; cētasō = minded; hi = certainly; asu = soon; buddhiḥ = wisdom; pari = sufficiently; avatiṣṭhati = gets established;]
One who has become free from passion and hatred, in-spite of the material topics coming in contact with indriyas freely, who has got indriyas under his grasp, who has made indriyas his servant, obtains grace, i.e. serenity of mind. From that grace, destruction of all miseries becomes possible. Certainly that serene minded, soon gets himself established in sufficient wisdom.
Note: Even though we loosely translate 'indria' as 'senses', in the Indian philosophical system 'indriya' always refers collectively to five senses, jnanēndriy , i.e. organs of senses, five functional organs, karmēndriya , i.e. organs of action, and the mind, ubhayēndriya , organ that has dual function of sensing and action, totalling eleven in number.
Gīta Bhāshya 2.64 and 65
The two verses describe results of conquering the 'indriyas'. 'vidhēya ātmā' - one who has conquered the mind even while experiencing material topics. 'prasādaṁ' - serenity of mind. Grace ('prasāda') results from the touch of transcendental Brahman. Thus, senses on their own are not drawn towards material topics, resulting in elimination of misery.
इंद्रियजयफलम् आह उत्तराभ्यां श्लोकाभ्याम्। विषयान् अनुभवन्नपि। विधेय आत्मा मनः अस्य सः जितात्मेत्यर्थः। प्रसादं मनःप्रसादम् ॥ ६४ ॥
कथं प्रसादमात्रेण सर्वदुःखहानिः। प्रसन्नचेतसो हि बुदि्धः पर्यवतिष्ठति ब्रह्मापरोक्ष्येण सम्यक् स्थितिं करोति। प्रसादो नाम स्वतोपि प्रायः विषयागतिः ॥६५॥
[iṁdriyajayaphalam āha uttarābhyāṁ ślōkābhyām। viṣayān anubhavannapi। vidhēya ātmā manaḥ asya saḥ jitātmētyarthaḥ। prasādaṁ manaḥprasādam ॥ 64 ॥]
kathaṁ prasādamātrēṇa sarvaduḥkhahāniḥ। prasannacētasō hi budidhaḥ paryavatiṣṭhati brahmāparōkṣyēṇa samyak sthitiṁ karōti। prasādō nāma svatōpi prāyaḥ viṣayāgatiḥ ॥65॥
[iṁdriyajayaphalam = results obtained by conquering the 'indriyas'; āha = is described; uttarābhyāṁ = in next; ślōkābhyām = two verses; viṣayān = material topics; anubhavannapi = even while experiencing; vidhēya ātmā = 'vidhēya ātmā' means; manaḥ = the mind; asya saḥ = of his; jitātmētyarthaḥ = has been conquored; prasādaṁ = 'prasādaṁ', i.e. the serenity; manaḥprasādam = refers to the serenity of mind;]
[kathaṁ = how; prasādamātrēṇa = by only grace; sarvaduḥkhahāniḥ = destruction of all miseries; prasannacētasō = one who has a serene mind; hi = certainly; budidhaḥ = the wisdom; paryavatiṣṭhati = is stable without movement; brahmāparōkṣyēṇa = by the touch of transcendental Brahman; samyak = well; sthitiṁ = state; karōti = is achieved; prasādō = grace; nāma = not, is; svatōpi = on its own; prāyaḥ = almost; viṣayāgatiḥ = movement towards material topics;]
The results obtained by conquering the 'indriyas' is described in next two verses. 'vidhēya ātmā' means the one who has conquered the mind even while experiencing material topics. 'prasādaṁ', i.e. serenity, here refers to the serenity of the mind.
How only by grace destruction of all miseries is possible? Because, one who has the serene mind certainly has stable well established wisdom resulting from the touch of transcendental Brahman. Grace (prasāda) means on its own, (the senses), are not drawn towards material topics.